Explanation

A triangle is called a right-angled triangle when it has an angle equal to 90 degrees.

Otherwise, it will not be a right-angled triangle.

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all four sides are of equal length (equilateral), and all four angles are right angles. 

A triangle that has no equal sides and no equal angles is known as a Scalene Triangle

while 

if two sides of a triangle are of equal length, then it is called. Isosceles triangle

Sh5-9-2023